B roads are numbered routes in Great Britain of lesser importance than
A roads. See the article
Great Britain road numbering scheme
The Great Britain road numbering scheme is a numbering scheme used to classify and identify all roads in Great Britain.
Each road is given a single letter (which represents the road's category) and a subsequent number (between 1 and 4 digits). ...
for the rationale behind the numbers allocated.
B300 to B399
B3000 to B3099
B3100 to B3199
.
B3200 to B3299
B3300 to B3399
B3400 to B3499
Footnotes
References
{{DEFAULTSORT:B Roads In Zone 3 Of The Great Britain Numbering Scheme
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